respiration

• Respiration is a multistep biochemical process of oxidative breakdown of organic compounds inside living cells releasing small packets of energy.
• The respiratory substrate is glucose.
• During vigorous exercise, pyruvate gets converted to lactic acid which leads to muscle cramps.
• The first step in both aerobic and anaerobic respiration takes place in the cytoplasm i.e. the breakdown of glucose into a three carbon compound known as pyruvate.
• The energy released during cellular respiration is immediately used to synthesize a molecule called ATP. It is the energy currency for most cellular processes.
• The energy released during the process of respiration is used to make an ATP molecule from ADP and inorganic phosphate.
• Since the amount of dissolved oxygen in water is lesser as compared to atmospheric oxygen the rate of breathing in aquatic organisms is faster as compared to terrestrial ones.
• The human respiratory system involves the nose, nasal cavities, pharynx, larynx, trachea/windpipe, bronchi, bronchioles and alveoli.
• Air is taken into the body through nostrils. The air gets filtered by fine hairs and mucus that lines the passage.

  From here the air passes through the trachea which is guarded by rings of cartilage to prevent collapsing.

  Bronchi divides into smaller branches called bronchioles which finally terminate in balloon like structures known as alveoli which provides the surface for exchange of gases.
• why is the trachea guarded by rings of cartilage?

  rings of cartilage prevent the trachea from collapsing.
• Breathing in humans is facilitated by the action of muscles attached to the ribs and the diaphragm.
• When the dome-shaped diaphragm contracts and becomes flattened and the rib cage is expanded, the volume of the lungs increases and the air from outside gushes in. This is inhalation.
• Exchange of gases through the alveoli takes place due to diffusion.
• Hemoglobin present in red blood corpuscles has high affinity for oxygen.
• The upper respiratory tract is provided with small hair like structures called cilia. These cilia help to remove dust, germs and other harmful particles from inhaled air.